Use this brew bag when you want to start all - grain brewing with a single setup. It's perfect for homebrewers who want an easy - to - use and durable solution. The bag fits 30 - 42 quart kettles with diameters between 13' and 16' and up to 16.5' in height. It can also be used as a hop bag. Just make sure to keep the handles away from open flames outside the kettle to avoid scorching.